The present invention relates to remote starting systems for internal combustion engines and is particularly directed towards a radio controlled system for the remote ignition of such an engine in a manner such as to provide more control over the starting sequence thereof than has been previously possible.
It is well known that under the circumstances of cold, wet, or otherwise inclement weather the internal combustion engine of an automobile, truck, etc., can be very difficult to start or may be to some degree inaccessable when weather conditions are extreme. A relatively heavy snow, for example, especially under extremely cold temperatures makes it quite inconvenient to get to, clean off and start a frozen, snow covered automobile. In many instances, it is necessary to make at least two trips out to the vehicle, the first trip approximately fifteen minutes to a half-hour prior to using the car to get it started, allowing it to warm up to operating temperature before use.
Remote control starting systems have been disclosed in the prior art and in many cases utilize long cables which are used to transmit control signals to the automatic starter system and which cables must be laid, for example, from the automobile to the inside of the home in anticipation of inclement weather conditions. In some instances, radio control has replaced such cable connected control units and the automatic starter system is activated by radio signals. In one of these systems, that disclosed in U.S. Pat. No. 3,577,164, transmitted radio signals may comprise a plurality of audio frequencies which are effective to perform particular functions in the automatic system. In that disclosure, it is necessary to transmit several distinct radio signals, a first one of which is purely a check signal to establish that the automobile is within range of the transmitter whereby a second signal is provided to energize the automobile ignition circuit and a third transmitted radio signal functions to actuate a gas-pedal solenoid to supply fuel to the engine. Such use of a plurality of transmitted signals each performing an isolated function increases the possibility of one or more of these functions causing difficulty and inhibiting the entire starting sequence.
In other prior art systems such as in U.S. Pat. No. 3,553,472, an optional radio control unit may be utilized to send a plurality of signals each with a different frequency and each capable of initiating a particular function. In this system, as in the one described above, the starting sequence is not fully automatic in that each stage must be separately initiated by transmission of a distinct signal.